Historical Linguistics and Language Families 2, Exercise 2: types of change

Latin kom- > con-          assimilation (the m takes the place of the next
                           consonant)
thridda > third            metathesis (the r and the vowel switch places)
humilis > humble           epenthesis (a sound, b, is inserted)
Englaland > England        haplology (a syllable next to a similar one is
                           removed)
status > estado (Spanish)  prothesis (a sound, e, is added at the start)

All five examples are from Wikipedia, Sound change.